a f100/f70 can be docked at an airbridge provided the cabin crew lowers the door (with stairs on the inside) first and then they have to lower the side bars (they form the rail were pax hold on to). After this the cabin crew also lowers a kind of hatch . When this is done, the jetway is to be positioned as normal. Also note that not all these f100/f70 have the incorporated airstairs. Some a/c have doors that open like for instance b737 or md80